A modern prewar building” is how director of sales Stacey Greenfield describes 47 E. 91st St., a Carnegie Hill building under construction with eight condominiums that start at $5,365,000 and go up to $14,525,000.

Greenfield’s phrase might seem like a contradiction in terms, but then again, this neighborhood has always embraced change slowly.

Developer Cary Tamarkin learned this firsthand when his initial plans for a 17-story high-rise on the site were met with howls of protest. As might be expected in an area known as an enclave for the rich and famous, the complaints were backed by star power.

Woody Allen (whose townhouse a block away from the new development recently went on the market) made a short film to voice his displeasure. Jurate Kazickas, co-chairwoman of the CitiNeighbors Coalition of Historic Carnegie Hill, brought neighborhood celebs like Paul Newman, Bette Midler and Kevin Kline on board in the fight against the building. Sir Howard Stringer, chairman of Sony, also voiced his concerns.

In the end, 17 stories became 10, and the neighborhood held its collective breath, hoping for a structure that would leave the area’s charms intact.

Actually, the end might not yet have come, even though four of the units have already been sold and residents should be moving in next April. According to Kazickas, the legal challenge against the building is ongoing. Tamarkin’s lawyer, Bob Davis, confirms that arguments in this latest round of appeals are set to begin this February.

It’s with good reason then that Greenfield is quick to mention the building’s “prewar” credentials. And with generous proportions and features like plaster moldings and oversize fireplaces, the development does resemble the grand old buildings of the 1920s.

Of course, there are modern touches. In addition to old-school flourishes like burnished brass doorknobs, the apartments come pre-wired for high-speed Internet access. An advanced multi-zoned heating and air-conditioning system gives residents precise climate control. And a state-of-the-art security system gives residents peace of mind.

Boasting five bedrooms and five-and-a-half baths per unit, the condos were designed with children in mind, and most of the interest thus far has indeed come from young families.

With all units topping 4,000 square feet (the penthouse offers 6,000 square feet plus a 2,000-square-foot terrace), there’s plenty of room for growth. And given the building’s proximity to some of the city’s finest schools (the Dalton and Spence schools sit within a block), its appeal to parents is easy to understand.

Inside, European marble and English white oak grace the floors of each apartment; enormous casement windows flood the rooms with sunlight; outrageously large master bedrooms look out onto private gardens.

Outside the lobby doors, however, reviews of the building are less stellar.

“I still think it’s inappropriate in scale compared to the charming townhouses on Madison,” says Kazickas. “It’s too hulking, kind of looming. We just wish it wasn’t there.”